Suggestions on an easy to use NAS

Looking for suggestions on an easy to use NAS. Something that is autonomous, simply plugs into another computer, acts as a single drive, has failure protection (RAID6, for example) and a minimum of 4-5 bays. If this doesn't exist, tell me I'm dreaming. I really don't want to bother setting up my own software and arrays, so this is what I'm hoping to get.

Currently running 2 x 2TB and 4 x 1TB drives as individual drives under Windows 7 with no failure protection and limited SATA ports. It's working fine, but would like to expand storage (new bigger drives) and get these drives out of my main rig so I can run a cooler, quieter main rig with the NAS tucked away in another room.

Not sure what price these run, but cheaper is better. No enterprise class stuff!

Synology makes good stuff. We've also gotten a couple iomega devices in at the office, pretty cool little guys as well.

Mmm. $930 for an 8 bay with no disks seems like a lot. Not that I expect 8 drives for that money, but the device itself seems expensive.

I have no clue about this brand, but I ran across this unit made by Mediasonic. I understand that that is a 4 bay unit with USB 3.0 and an on-board RAID 5 controller. I think there is also a 8 bay unit, but I would be scared running only RAID 5.

Do you need features like dynamic expansion or drive failure reporting? It appears that this unit does not have it. But at $200, I would consider buying two and having a properly backed up pool of data...